For
ecosystems, the major source of energy is sunlight. Energy entering
ecosystems as sunlight is transferred by producers into chemical
energy through photosynthesis. That energy then passes from
organism to organism in food webs. (5-8)

Earth
and Space Science

The
sun provides light and heat necessary to maintain the temperature
of the earth.

Weather
changes from day to day and over the seasons.

The
sun is the major source of energy for phenomena on the earth's
surface, such as growth of plants, winds, ocean currents, and
the water cycle. (5-8)